TaskGraphRunner Group support

cc/raster/tile_task_worker_pool_perftest.cc

Index: cc/raster/tile_task_worker_pool_perftest.cc
diff --git a/cc/raster/tile_task_worker_pool_perftest.cc b/cc/raster/tile_task_worker_pool_perftest.cc
index 70902c845c8293521d05ca4cf7829a0b228f60a4..6a57f63f291d8819f6b880100b3df97cd7e87798 100644
--- a/cc/raster/tile_task_worker_pool_perftest.cc
+++ b/cc/raster/tile_task_worker_pool_perftest.cc
@@ -223,13 +223,14 @@ class TileTaskWorkerPoolPerfTestBase {
 
       for (auto& decode_task : raster_task->dependencies()) {
         graph->nodes.push_back(
-            TaskGraph::Node(decode_task.get(), priority, 0u));
+            TaskGraph::Node(decode_task.get(), 0u /* group */, priority, 0u));
         graph->edges.push_back(
             TaskGraph::Edge(raster_task.get(), decode_task.get()));
       }
 
-      graph->nodes.push_back(TaskGraph::Node(
-          raster_task.get(), priority, raster_task->dependencies().size()));
+      graph->nodes.push_back(
+          TaskGraph::Node(raster_task.get(), 0u /* group */, priority,
+                          raster_task->dependencies().size()));
     }
   }